Membrane resonance enables stable and robust gamma oscillations

Neuronal mechanisms underlying beta/gamma oscillations (20-80 Hz) are not completely understood. Here, we show that in vivo beta/gamma oscillations in the cat visual cortex sometimes exhibit remarkably stable frequency even when inputs fluctuate dramatically. Enhanced frequency stability is associated with stronger oscillations measured in individual units and larger power in the local field potential. Simulations of neuronal circuitry demonstrate that membrane properties of inhibitory interneurons strongly determine the characteristics of emergent oscillations. Exploration of networks containing either integrator or resonator inhibitory interneurons revealed that: (i) Resonance, as opposed to integration, promotes robust oscillations with large power and stable frequency via a mechanism called RING (Resonance INduced Gamma); resonance favors synchronization by reducing phase delays between interneurons and imposes bounds on oscillation cycle duration; (ii) Stability of frequency and robustness of the oscillation also depend on the relative timing of excitatory and inhibitory volleys within the oscillation cycle; (iii) RING can reproduce characteristics of both Pyramidal INterneuron Gamma (PING) and INterneuron Gamma (ING), transcending such classifications; (iv) In RING, robust gamma oscillations are promoted by slow but are impaired by fast inputs. Results suggest that interneuronal membrane resonance can be an important ingredient for generation of robust gamma oscillations having stable frequency

The ethical and socially responsible behavior of the commercial companies

In the Romanian society and economy the need to distinguish certain behaviors based on the principles of ethics and social responsibility becomes obvious. The totality of the decisions made by the commercial companies must ensure the observance of the interests of all entities which interact with these. The situation of each commercial company whose decisions are inconsistent with the requirements of ethics and social responsibility will sooner or later be endangered because it affects the interests of others, it means in fact affecting one’s own interests

EEG processing with TESPAR for depth of anesthesia detection

Poster presentation: Introduction Adequate anesthesia is crucial to the success of surgical interventions and subsequent recovery. Neuroscientists, surgeons, and engineers have sought to understand the impact of anesthetics on the information processing in the brain and to properly assess the level of anesthesia in an non-invasive manner. Studies have indicated a more reliable depth of anesthesia (DOA) detection if multiple parameters are employed. Indeed, commercial DOA monitors (BIS, Narcotrend, M-Entropy and A-line ARX) use more than one feature extraction method. Here, we propose TESPAR (Time Encoded Signal Processing And Recognition) a time domain signal processing technique novel to EEG DOA assessment that could enhance existing monitoring devices. ..

Multidimensional patterns of neuronal activity: how do we see them?

Poster presentation: Introduction The brain is a highly interconnected network of constantly interacting units. Understanding the collective behavior of these units requires a multi-dimensional approach. The results of such analyses are hard to visualize and interpret. Hence tools capable of dealing with such tasks become imperative. ...

Effect of pipe diameter in piping system using acoustic emission technique

This project was carried out as a study of effect of pipe diameter different and different pressure in piping system by using Acoustic Emission technique. The objective of this research is to investigate the flow rate in the piping system due to the pipe diameter difference and pressure different and evaluates type of signal produce from the acoustic emission technique for each type of pipe diameter in piping systems. A test rigs consist of a galvanized steel pipe that have two different diameters to run the experiments. The liquid that has been used is water and it controlled by the ball valve to setting the three different pressures. The source of the AE signal was from the ball valve that controlled the pressure but the effect of different diameter also play it roll because it can give a different flow rate that will show either the flow of water is low or high turbulent flow. The signal was captured using AE sensor with help of Acoustic Emission Detector 2.1.3 software. For all pipe diameter and pressure, the values of hits, counts and RMS (average, minimum and maximum) were recorded and analyzed. All the value recorded was compared to the different of pipe diameter and different pressure. The result shows that there almost no AE activities on the pipe that has big diameter compare to the smaller one. The conclusion has shown that the big pipe diameter will secure the safety because of the flow of the water that enter the pipe is low in flow rate and produced low turbulent flow compare to the small pipe diameter